Attention can be directed to a visual location covertly without movements of head and eyes. It is possible to time lock shifts of covert attention to the occurrence of cues telling where in space a target event is most likely to occur. Although orienting seems to be a simple integrated act there are a number of components that are profoundly affected by certain forms of brain injury. We plan to study in detail how such injuries interrupt the ability to orient attention. To do so we will examine patients with left and right parietal and frontal lesions comparing their performance in detecting targets insilateral and contralateral to the lesion following valid and invalid cues. We will examine how such lesions interrupt covert orienting processes. These studies should provide a deeper undertanding of normal attention, show how deficits result from brain injury and supply more sensitive tests to assay efforts at remediation. A major goal of our proposal is the development of sufficiently detailed relationships between components of attention and brain systems so predictions and applications can be made to functional disorders that relate to issues of mental health. These include problems of depression, schizophrenia, attentional disorder deficits and other mental health problems that have been related to attentional difficulties.